高压直流详细仿真模型CIGRE HVDC Detailed modeling

Detailed Modeling of CIGRéHVDC Benchmark System Using PSCAD/EMTDC and PSB/SIMULINK M.O.Faruque,Student Member,IEEE,Yuyan Zhang,and Venkata Dinavahi,Member,IEEE

Abstract—This paper focuses on a comparative study of the mod-eling and simulation of the?rst CIGRéHVDC benchmark system using two simulation tools PSCAD/EMTDC and PSB/SIMULINK; an interface between them(PSCAD-SIMULINK)has also been im-plemented and used as a simulator.The CIGRéHVDC system and its controller has been carefully modeled in all three simulation environments so that the differences are https://www.sodocs.net/doc/924165428.html,parison of steady-state and transient situations have been carried out,and a high degree of agreement in most of the cases has been observed. Index Terms—HVDC transmission,modeling,simulation.

I.I NTRODUCTION

T HE DESIGN,analysis,and operation of complex ac-dc systems require extensive simulation resources that are accurate and reliable.Analog simulators,long used for studying such systems,have reached their physical limits due to the increasing complexity of modern systems.Currently,there are several industrial grade digital time-domain simulation tools available for modeling ac-dc power systems.Among them,some have the added advantages of dealing with power electronics apparatus and controls with more accuracy and ef?ciency.PSCAD/EMTDC[1]and PSB/SIMULINK[2]are such two simulators that are being increasingly used in the industry as well as in the universities.Both programs allow the user to construct schematic diagram of electrical networks, run the simulation,and produce the results in a user-friendly graphical environment.Furthermore,several real-time digital simulators use models or the graphical front-end that are similar to PSCAD/EMTDC and PSB/SIMULINK.

The objective of this paper is to report a detailed compar-ison between PSCAD/EMTDC and PSB/SIMULINK for the modeling and simulation of ac-dc power systems.In a digital simulator,the system model and the algorithm used to solve that model directly affect the accuracy and consistency of the sim-ulation results.Therefore,based on the objective of the study, careful attention should be given to the selection of the model, the numerical solver,and the algorithm.A comparative study among simulation tools will help in identifying the pros and cons that the programs inherit.For the last two decades,digital simulators have been widely used for the simulation of HVDC

Manuscript received September1,2004;revised December4,2004.This work was supported by the Natural Sciences and Engineering Research Council (NSERC)of Canada and the University of Alberta.Paper no.TPWRD-00406-2004.

The authors are with the Electrical and Computer Engineering Depart-ment,University of Alberta,Edmonton,AB T6G2V4,Canada(e-mail: faruque@ece.ualberta.ca;yuyan@ece.ualberta.ca;dinavahi@ece.ualberta.ca). Digital Object Identi?er10.1109/TPWRD.2005.852376and its control system.However,to compare the performance of any two simulators,similar circuit topology with control is a prerequisite.To achieve that goal,a benchmark system for HVDC,known as the CIGRéBenchmark Model,was proposed in1985[3].It provided a common reference system for HVDC system https://www.sodocs.net/doc/924165428.html,ter in1991,a comparison of four digital models has been carried out by the CIGRéWorking Group[4],[5],and a benchmark system for HVDC control study was also proposed.A detailed comparison between ATP and NETOMAC for the simulation of HVDC system was?rst reported in[6],where the fundamental differences between the two software and their effects on simulation results have been discussed.The study found a good agreement between the two simulation results.More recently,custom power con-trollers such as DSTATCOM and DVR have been simulated [7]using PSCAD/EMTDC and SIMULINK to compare their performance.However,for a rigorous comparison between simulation tools and to gain insight into their capabilities and limitations,the modeled system should be able to offer the highest degree of dif?culty.The main motivation for using the CIGRéBenchmark HVDC System in this paper is that not only is it a widely used test system but also it is complex enough, with deliberate dif?culties introduced for a comprehensive performance evaluation of the two simulation tools.

Section II of this paper gives a brief introduction about the two simulation tools highlighting their solution techniques, and Section III introduces the CIGRéHVDC benchmark system.Sections IV–VI present the detailed model of HVDC system and its controller in three simulation environments: PSCAD/EMTDC,PSB/SIMULINK,and PSCAD-SIMULINK interface.Results are presented in Section VII,followed by conclusions in Section VIII.

II.PSCAD/EMTDC AND PSB/SIMULINK PSCAD/EMTDC is a powerful time-domain transient sim-ulator for simulating power systems and its controls.It uses graphical user interface to sketch virtually any electrical equip-ment and provide a fast and?exible solution.PSCAD/EMTDC represents and solves the differential equations of the entire power system and its control in the time domain(both elec-tromagnetic and electromechanical systems)[8].It employs the well-known nodal analysis technique together with trapezoidal integration rule with?xed integration time-step.It also uses in-terpolation technique with instantaneous switching to represent the structural changes of the system[9],[10].

MATLAB/SIMULINK is a high-performance multifunc-tional software that uses functions for numerical computation,

0885-8977/$20.00?2006IEEE

Fig.1.Single-line diagram of the CIGRébenchmark HVDC system.

system simulation,and application development.Power System Blockset(PSB)is one of its design tools for modeling and simulating electric power systems within the SIMULINK environment[2],[11].It contains a block library with common components and devices found in electrical power networks that are based on electromagnetic and electromechanical equations.PSB/SIMULINK can be used for modeling and simulation of both power and control systems.PSB solves the system equations through state-variable analysis using either ?xed or variable integration time-step.The linear dynamics of the system are expressed through continuous or discrete time-domain state-space equations.It also offers the?exibility of choosing from a variety of integration algorithms.

III.F IRST CIGRéHVDC B ENCHMARK S YSTEM

The?rst CIGRéHVDC benchmark system shown in Fig.1 was proposed in[3].The system is a mono-polar500-kV, 1000-MW HVDC link with12-pulse converters on both rec-ti?er and inverter sides,connected to weak ac systems(short circuit ratio of2.5at a rated frequency of50Hz)that provide a considerable degree of dif?culty for dc controls.Damped ?lters and capacitive reactive compensation are also provided on both sides.The power circuit of the converter consists of the following subcircuits.

A.AC Side

The ac sides of the HVDC system consist of supply net-work,?lters,and transformers on both sides of the converter. The ac supply network is represented by a Thévénin equivalent voltage source with an equivalent source impedance.AC?lters are added to absorb the harmonics generated by the converter as well as to supply reactive power to the converter.

B.DC Side

The dc side of the converter consists of smoothing reactors for both recti?er and the inverter side.The dc transmission line is represented by an equivalent T network,which can be tuned to fundamental frequency to provide a dif?cult resonant condition for the modeled system.C.Converter

The converter stations are represented by12-pulse con?gura-tion with two six-pulse valves in series.In the actual converter, each valve is constructed with many thyristors in series.Each valve has

a limiting inductor,and each thyristor has par-allel RC snubbers.

IV.CIGRéHVDC S YSTEM M ODEL IN PSCAD

The full three-phase model of the CIGRéHVDC benchmark system is available as an example?le in PSCAD/EMTDC Ver-sion4.0.1.Data for the CIGRéHVDC benchmark system[4],

[5]is given in Table V.

A.Power Circuit Modeling

1)Converter Model:The converters(recti?er and inverter) are modeled using six-pulse Graetz bridge block,which in-cludes an internal Phase Locked Oscillator(PLO),?ring and valve blocking controls,and?ring

angle/extinction

angle measurements.It also includes built-in RC snubber circuits for each thyristor.Thyristor valves are modeled as ideal devices, and therefore,negative turn-off and?ring due to

large

or are not considered.

2)Converter Transformer Model:Two transformers on the recti?er side are modeled by three-phase two winding trans-former,one with grounded Wye–Wye connection and the other with grounded Wye–Delta connection.The model uses satura-tion characteristic and tap setting arrangement.The inverter side transformers use a similar model.

3)DC Line Model:The dc line is modeled using an equiva-lent-T network with smoothing reactors inserted on both sides.

4)Supply Voltage Source:The supply voltages on both rec-ti?er and inverter sides have been represented through three-phase ac voltage sources.

5)Filters and Reactive Support:Tuned?lters and reactive support are provided at both the recti?er and the inverter ac sides,as shown in Fig.1.

B.Control System Model

The control model mainly consists

of measurements and generation of?ring signals for both the recti?er and inverter. The PLO is used to build the?ring signals.The output signal of the PLO is a ramp,synchronized to the phase-A commutating

bus line-to-ground voltage,which is used to generate the ?ring signal for Valve 1.The ramps for other valves are generated by adding 60to the Valve 1ramp.As a result,an equidistant pulse is realized.The actual ?ring time is calculated by comparing

the order to the value of the ramp and using interpolation [10]technique.At the same time,if the valve is pulsed but its voltage is still less than the forward voltage drop,this model has a logic to delay ?ring until the voltage is exactly equal to the forward voltage drop.The ?ring pulse is maintained across each valve for 120.

The

and measurement circuits use zero-crossing informa-tion from commutating bus voltages and valve switching times and then convert this time difference to an angle (using mea-sured PLO frequency).Firing

angle (in seconds)is the time when valve turns on minus the zero crossing time for valve .Extinction

angle (in seconds)for valve is the time at which the commutation bus voltage for valve crosses zero (negative to positive)minus the time valve turns off.The control schemes for both recti ?er and inverter of the CIGR éHVDC system are available in the example ?le in PSCAD/EMTDC Version 4.0.1.Following are the controllers used in the control schemes:

?Extinction

Angle

Controller;?dc Current Controller;

?V oltage Dependent Current Limiter (VDCOL).

1)Recti?er Control:The recti ?er control system uses Con-stant Current Control (CCC)technique.The reference for cur-rent limit is obtained from the inverter side.This is done to en-sure the protection of the converter in situations when inverter side does not have suf ?cient dc voltage support (due to a fault)or does not have suf ?cient load requirement (load rejection).The reference current used in recti ?er control depends on the dc voltage available at the inverter side.Dc current on the recti ?er side is measured using proper transducers and passed through necessary ?lters before they are compared to produce the error signal.The error signal is then passed through a PI controller,which produces the necessary ?ring angle

order .The ?ring circuit uses this information to generate the equidistant pulses for the valves using the technique described earlier.

2)Inverter Control:The Extinction Angle Control

or con-trol and current control have been implemented on the inverter side.The CCC with V oltage Dependent Current Order Limiter (VDCOL)have been used here through PI controllers.The ref-erence limit for the current control is obtained through a com-parison of the external reference (selected by the operator or load requirement)and VDCOL (implemented through lookup table)output.The measured current is then subtracted from the reference limit to produce an error signal that is sent to the PI controller to produce the required angle order.

The control uses another PI controller to produce gamma angle order for the inverter.The two angle orders are compared,and the minimum of the two is used to calculate the ?ring instant.

V .CIGR éHVDC S YSTEM M ODEL IN PSB

The CIGR éHVDC system model developed using PSB/SIMULINK Version 6.5release 13is shown in Fig.9.To implement this model,a total of 106states,37inputs,112outputs,and 31switches were used.

A.Power Circuit Modeling

The recti ?er and the inverter are 12-pulse converters con-structed by two universal bridge blocks connected in series.The converter transformers are modeled by one three-phase two winding transformer with grounded Wye –Wye connection,the other by three-phase two winding transformer with grounded Wye –Delta connection.The converters are interconnected through a T-network.

1)Universal Bridge Block:The universal bridge block im-plements a universal three-phase power converter that consists of six power switches connected as a bridge.The type of power switch and converter con ?guration can be selected from the di-alog box.Series RC snubber circuits are connected in parallel with each switch device.The vector gating signals are six-pulse trains corresponding to the natural order of commutation.

The

and measurements are not realized in this model.

2)Three Phase Source:A three-phase ac voltage source in series with a R-L combination is used to model the source,and its parameters are set as in Table V .

3)Converter Transformer Model:The three-phase two winding transformers models have been used where winding connection and winding parameters can be set through mask parameters.The tap position is at a ?xed position determined by a multiplication factor applied on the primary nominal voltage of the converter transformers (1.01on recti ?er side;0.989on inverter side).The saturation has been simulated.The saturation characteristic has been speci ?ed by a series of current/?ux pairs (in p.u.)starting with the pair (0,0).

The dc line,ac ?lters,and reactive support are similar to the ones used in the PSCAD/EMTDC model.B.Control System Model

The control blocks available in SIMULINK have been used to emulate the control algorithm described in Section IV-B,and enough care has been taken to ensure that exact parameters as in PSCAD/EMTDC simulation are used.Some control param-eters required conversion to their proper values due to differ-ences in units.The recti ?er side uses current control with a ref-erence obtained from the inverter VDCOL output (implemented through a lookup table),and the inverter control has both cur-rent control

and control operating in parallel,and the lower output of the two is used to generate the ?ring pulses.Unlike PSCAD/EMTDC,the

angle is not provided directly from the converter valve data.It needed to be implemented through mea-surements taken from valve data.The control block diagrams are shown in Fig.2.

VI.PSCAD-SIMULINK I NTERFACE

PSCAD Version 4.0.1has the capability of interfacing with MATLAB/SIMULINK commands and toolboxes through a special interface.MATLAB programs or block-sets that would be interfaced,with PSCAD needing to be designed and saved as a MATLAB program ?le or as a SIMULINK block ?le.Then,a user-de ?ned block must be provided in PSCAD,with the neces-sary inputs and outputs,to interface the MATLAB/SIMULINK ?le.In this paper,the power circuit of CIGR éHVDC system has been modeled in the PSCAD/EMTDC environment while

Fig.2.CIGR éHVDC control system in SIMULINK.(a)Recti ?er control.(b)Gamma measurement.(c)Inverter control.

the control system has been modeled using block-sets from PSB and the SIMULINK Control Library.An interfacing block has been created in PSCAD/EMTDC that linked the SIMULINK ?les through FORTRAN scripts de ?ned within the block.A reverse scenario,where the power circuit is mod-eled in PSB/SIMULINK and the control system is modeled in PSCAD/EMTDC,is also feasible.Fig.3shows the block diagram of PSCAD-SIMULINK interface used to simulate CIGR éHVDC system.The time step used for the simulation is

50;the two programs exchange information between them continuously at every time step.

VII.S IMULATION R ESULTS

With the goal of performing a rigorous comparative study among the simulation tools,the CIGR éHVDC system has been simulated in three environments:1)using PSCAD/EMTDC only;2)using PSB/SIMULINK only;

3)using the PSCAD-SIMULINK Interface.

Steady-state and transient results (created through various faults)were recorded and then compared.The comparison reveals a high degree of similarity among the results obtained through the three simulation environments with minor discrep-ancies.A.Steady State

For steady-state analysis,the system has been simulated for a duration of 2s in all three simulation environments.There were some initial transients that subsided within about 0.5s and the system reached steady state.

1)DC Voltages and Currents:Fig.4shows the results where the ?rst column is produced by PSCAD/EMTDC,the second from PSB/SIMULINK,and the third by the PSCAD-SIMULINK interface.Row-wise,the ?rst row shows the recti ?er dc voltage produced by the three simulation tools;the second and fourth row are the magni ?ed view of dc voltages on both the recti ?er and inverter side;the third and ?fth

row

Fig.3.PSCAD-SIMULINK interface.

show the harmonic spectrum.The following observations can be made from Fig.4.

?For both inverter and recti ?er,the dc voltages show small oscillations around the reference value (1p.u);however,they are almost identical,except for minor differences at start-up.During initialization,PSCAD/EMTDC and PSCAD-SIMULINK interface do not show any negative dc voltage,whereas PSB/SIMULINK shows a negative

transient

p.u .However,all three simulation tools have produced identical waveforms in terms of phase and magnitude in steady state,and there is hardly any discrep-ancy among them.The zoomed view of their steady-state waveforms re ?ects that fact.

?The mean of output dc voltage produced by PSCAD/EMTDC and PSCAD-SIMULINK interface falls short of reference outputs by (1–2)%(0.99p.u.for PSCAD/EMTDC and 0.98p.u.for PSCAD-SIMULINK interface),whereas it is 1.0p.u.for PSB/SIMULINK.?The Fourier spectrum of the corresponding waveforms have very few differences.The dc component is close to 1.0for all environments,but in the plot,it is not shown in full magnitude,for the sake of highlighting the harmonics

Fig.4.Steady-state results for dc voltage.

TABLE I

C OMPARISON OF THD(%),M EAN,AN

D MAD FOR DC V OLTAGES AND C URRENTS P RODUCED BY D IFFERENT S IMULATION T

OOLS

present in the signal.The THDs found in the three cases for different waveforms are also very close.

?Table I shows further information about the?ne differ-ences in terms of mean value,THD,and Mean Absolute Deviation(MAD).Close results have also been observed for dc currents on both the recti?er and inverter sides. 2)AC Voltages and Currents:All ac side waveforms on both the recti?er and inverter sides have also been compared. The results were found to be similar,and only the ac current waveforms and their harmonic spectrum are shown in Fig.5. Both recti?er and inverter ac currents are similar in terms of phase angle and their magnitude;their spectrum is identical, which reaf?rms the accuracy of all three simulation techniques. The11th and13th harmonics are the dominant harmonics on both recti?er and inverter sides;their THDs have been found to be close for all simulation environments.Table II compares other control outputs

(,

inverter,and recti?

er). PSCAD-SIMULINK shows the maximum recti?

er(17.28), while PSB/SIMULINK shows the minimum(14.44).This result agrees with the mean value of the dc voltage produced on the recti?er side by the three simulation environments.Sim-ilarly,

for,PSCAD-SIMULINK shows the highest(15.72), and PSB/SIMULINK shows the lowest(14.95).However, these differences are small,and the produced results are con-sistent.

B.Transients

Dc and ac faults have been simulated in the three simula-tion environments.The instant and duration of faults have been

Fig.5.Steady-state results for ac currents on the recti ?er and inverter side.

TABLE II

C OMPARISON OF O UTPUTS P RODUCE

D BY C ONTROL S

YSTEMS

maintained the same for all types of faults,i.e.,the fault is ap-plied at 1.0s and cleared after 0.15s.The fault resistance has

been chosen as

0.1and

1

for fault-on and fault-off situa-tions,respectively.Clearing of the fault has been allowed,even when there is a fault current ?owing.

1)Dc Fault:This fault has been located at the midpoint of the dc line.Fig.6illustrates different output parameters of the system.The transient response in all three simulation environ-ments has been found almost similar.During the fault,the dc voltage has gone down to zero (the small oscillation is due to the energy stored in the capacitor),and a momentary transient dc current has been observed.However,control response forces recti ?

er and

inverter to reach maximum and

inverter to reach minimum,thereby reducing the current ?ow.VDCOL forces the current to stay minimum until the dc voltage situation is improved.Once the fault is cleared,the dc voltage is recov-

ered,and the control system brings the system back to normal operation.The transient response for all three simulation envi-ronments has been compared in terms of Rise Time (RT),Set-tling Time (ST),and Overshoot (OS)in Table III.

2)AC Faults:Two cases of ac faults have been simulated:One is a single line-to-ground fault (see Fig.7),and the other is a three-phase to ground fault (see Fig.8).Both are applied on the inverter side of the system.During fault,the dc voltage has gone down to zero (neglecting oscillation due to capacitor energy storage),the dc current faces a momentary overshoot,and then goes to minimum limit with some oscillation present (due to the oscillation of dc voltage).Recti ?

er ,

inverter ,and

inverter reach to maximum value,thereby blocking the system for the fault duration.Once the fault is cleared,the system comes back to its normal operation.During an ac fault,commutation failures happen,resulting in a momentary drop-down of dc voltage.This causes the VDCOL to limit the dc current to a minimum,and ac voltages also get disturbed (not shown in the ?gure).The voltage and current waveforms for the three environments are similar;however,the following minor discrepancies were observed.?In all three cases,the rise-time for inverter dc voltage for ac faults is shorter than that for the dc fault.Even though PSCAD/EMTDC and PSCAD-SIMULINK show

Fig.6.V oltages and currents under a short duration dc fault.

a faster rise than PSB/SIMULINK case,PSB/SIMULINK

reaches steady state before the other two cases.

?The highest transient values of inverter dc currents during the phase-to-ground fault are 2.58p.u.for PSCAD/EMTDC, 2.4p.u.for PSB/SIMULINK,and

2.39p.u.for PSCAD-SIMULINK.

?The peak value of inverter ac current for the single phase-to-ground fault is13.2kA for PSCAD/EMTDC, 14kA for PSB/SIMULINK,and13kA for PSCAD-SIMULINK.

?In case of the three-phase to ground fault,when the fault

is cleared

at,in all the three environments,the

system is brought back to normal operation within0.05 s;however,PSCAD/EMTDC and PSCAD-SIMULINK could not stabilize the system,i.e.,after a small over-shoot,the system collapses again,though it regains the control very fast,and the system stability is restored.

PSB/SIMULINK,however,does not show this behavior.

C.Execution Time and Memory

All three environments were run on a Pentium IV1.5–GHz processor running Windows2000operating system.The ex-ecution time was recorded from the Time Summary shown on the output window in PSCAD/EMTDC and by using the cputime function at the start and end of the simulation in PSB/https://www.sodocs.net/doc/924165428.html,rmation on memory usage was collected from the System Performance Monitor on Windows2000. Although resource requirements for both programs may not be the same,attempts have been made to allow no other programs except the system?les to run while the simulations were performed.Table IV shows the execution time and memory usage for the three environments.PSCAD/EMTDC was found to be the fastest environment,while PSCAD-SIMULINK Interface was the slowest.For a simulation duration of2s, PSCAD/EMTDC took30.5s with a memory usage of42 MB,whereas PSB/SIMULINK took72.2s with a memory usage of107MB.In comparison to these two environments, PSCAD-SIMULINK took a much longer execution time;using a

50sampling period in both PSCAD and SIMULINK environments,the execution time was found to be12503.58s with a memory usage of63MB(24MB for PSCAD and39MB for SIMULINK).The reason for such a long simulation time is the necessity of data exchange between the two programs at every

50;the memory usage for the interface was less than the other two environments due to the task partition(electrical system in PSCAD and control system in SIMULINK).A higher control sampling period reduced the execution time by a very small margin(2.5%for

100);however,it also reduced the accuracy of the simulation.

TABLE III

C OMPARISON OF R ISE T IME (RT)(S ),S ETTLING T IME (ST)(S ),AN

D O VERSHOOT (OS)(P .U .)D URING R ECOVERY F ROM A DC F

AULT

Fig.7.V oltages and currents under a short duration ac fault (phase-A to ground)on the inverter side.

D.General Remarks

Both PSCAD/EMTDC and PSB/SIMULINK provides user-friendly graphics for modeling power and control systems through simple functional blocks.However,the following minor differences particular to this case study,are worth men-tioning.

?PSCAD/EMTDC is a specialized software designed mainly for the analysis of ac/dc systems.Therefore,it has added advantages such as built-in PLO-based ?ring

control and the measurement

of

angles embedded inside the six-pulse Garetz bridge .On the other hand,PSB/SIMULINK requires these blocks and the measure-ment system to be developed by the user.

?PSB/SIMULINK offers more ?exibility in terms of choice of the solution techniques:?xed or variable time-step-

based solutions.However,for this study,a ?xed step-size trapezoidal rule has been used to be consistent with PSCAD/EMTDC.

?

The error debugging system in PSCAD/EMTDC is quite complex.In some cases,instead of locating the exact source of error,it returned general error messages.

VIII.C ONCLUSIONS

A detailed comparison of the performance of three simu-lation environments (PSCAD/EMTDC,PSB/SIMULINK,and PSCAD-SIMULINK Interface)has been demonstrated by mod-eling the CIGR éHVDC Benchmark System.All three environ-ments produced almost identical and consistent results during steady-state and transients situations,validating the accuracy of the modeling and solution algorithms.In terms of computational

Fig.8.V oltages and currents under a short duration ac fault(three-phase to ground)on the inverter side.

Fig.9.CIGRéHVDC benchmark system model in PSB/SIMULINK.

TABLE IV

E XECUTION T IME (ET)(S )AND M EMORY U SAGE (MU)(MB)FOR

A

S IMULATION D URATION OF 2S W ITH A T IME S TEP OF 50

s

TABLE V

CIGR éHVDC B ENCHMARK S YSTEM D

ATA

speed and memory usage,PSCAD/EMTDC was found to be the most ef ?cient environment.

A PPENDIX

Table V shows the CIGR éHVDC benchmark system data.

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M.O.Faruque (S ’03)received the B.Sc.Engg degree in 1992from Chittagong University of Engineering and Technology (CUET),Chittagong,Bangladesh,and M.Eng.Sc.degree in 1999from the University of Malaya,Kuala Lumpur,Malaysia,in the area of power engineering.He is working toward the Ph.D.degree from the Department of Electrical and Computer Engineering,University of Alberta,Edmonton,AB,Canada.

For the last ten years,he has been working in both academia and industry,and his research interests include FACTS,HVDC,and real-time digital simulation of power electronics and power systems.

Yuyan Zhang received the Bachelor ’s degree in electrical engineering from South-East University,Nanjing,China,in 1990and the M.E.degree from the University of Alberta,Edmonton,AB,Canada in 2003.

Since then,she has worked as an Electrical Engineer for a variety of indus-tries,including the Beijing Chemical Plant,Hongkong Well ?ne Ltd.,Motorola China Ltd.,and Siemens Ltd.,China,in the power generation group.Her re-search interests are in the area of power distribution systems,HVDC,and digital simulation.

Venkata Dinavahi (M ’00)received the B.Eng.degree in electrical engineering from Nagpur University,Nagpur,India,in 1993,the M.Tech.degree from the Indian Institute of Technology,Kanpur,India,in 1996,and the Ph.D.degree in electrical and computer engineering from the University of Toronto,Toronto,ON,Canada,in 2000.

Presently,he is an Assistant Professor at the University of Alberta,Edmonton,AB,Canada.His research interests include electromagnetic transient analysis,power electronics,and real-time simulation and control.

Dr.Dinavah is a member of CIGR éand a Professional Engineer in the Province of Alberta,Canada.

数据中心机房节能简析

数据中心机房节能简析 贾骏 吕捷 王众彪 工业和信息化部电信研究院 邮电工业产品质量监督检验中心 摘要：本文阐述了数据中心机房的主要能耗分布情况，并从数据设备、电源系统、空调系统、机房气流组织几个方面介绍了机房降耗的主要方式。 关键词：数据中心 UPS 气流组织 1、数据中心机房概述 数据中心是为集中式收集、存储、处理和发送数据的设备提供运行维护的设施以及相关的服务体系。数据中心提供的主要业务包括主机托管、资源出租、系统维护、管理服务，以及其他支撑、运行服务等。 本文所提到的数据中心机房，是指承载数据中心业务的基础设施，一般由核心业务机房、UPS机房、电池室、空调机房、柴油发电机房等构成。 我国数据中心市场发展迅速，根据赛迪顾问年度报告，2010年中国IDC市场规模达到102.2亿元。我国2005年以来数据中心市场发展的趋势如图1所示。 图1 我国IDC市场发展趋势 2、数据中心机房能耗分布 2010年我国数据中心资源投入占总投入将近30%，维护成本占总投入近15%。[1]2010年我国数据中心运营成本分布如图2所示。

图2 2010年中国IDC公司最高运营成本分析 数据中心机房能耗主要分为服务器/网络设备能耗、制冷能耗、供电系统能耗、照明和其他能耗。根据EYP Mission Critical Facilities所提供的数据，50%的数据中心用电量是被服务器/网络设备所消耗。制冷系统是数据中心内第二大能耗系统，其耗电量占数据中心总耗电量的37%。供电系统占10%，照明和其他占3%。[2] 3、数据设备降耗 数据设备是承载数据中心的业务核心设备，同时也是耗电量所占比例最大的设备。根据亚马逊JamesHamilton的研究，数据中心服务器硬件所消耗的电力的费用约占57%。针对不同规模的数据中心，该费用比例是不同的。2010年我国数据中心规模分布如图3所示。 图3 2010年中国IDC公司的机房服务器数量 服务器是数据中心最为常见的设备。使用高效低能耗的服务器是数据设备降耗的关键所在。Standard Performance Evaluation Corporation(SPEC) 是一个全球性的、权威的第三方应用性能测试组织，它制定了一系列的规范来评定服务器应用性能。可以根据SPEC的测试值评定服务器的效能/能耗，以此作为选购服务器的参考。另一个评定标准是能源之星的服务器标准，符合能源之星标准的服务器要比旧式服务器多出30%的能源效率。 对于网络设备，可以使用TEEER值以及ECR/EER性能能耗比评估法进行节能分析。 4、电源系统降耗

再论高压直流(HVDC )在数据机房的应用

再论高压直流（HVDC ）在数据机房的应用 摘要：数据中心首先应用在军事之上，随着社会科技不断发展、进步，逐渐在各个行业中使用，随着人们对数据的飞速增加的需求量，促进了通信行业在数据中心机房的建设压力，但庞大的数据市场，不可预估的数据增长趋势，也极大地刺激了通信行业、互联网行业在数据中心机房投入建设的决心，并付诸行动。而在数据中心机房的配电系统的建设中，从最初的简单的机械化的UPS 到安全系数高的系统，再逐步发展到高压直流配电系统，仅仅几十年。传统的UPS 电源，存在初始投资大，后期利用率低、可靠性差、运行能效低和维护困难等明显缺点。因此，作为UPS 的替代产品—高压直流电源（HVDC）便应运而生，而且越来越受到电源、通信等行业的重视。 关键词：数据机房；UPS供电系统；高压直流供电系统； 引言： 在本文，从UPS配电系统产生、原理及使用与高压直流配电系统分开叙述，剖析高压直流电源与UPS 电源对比和数据中心配电不同，完全地论述高压直流的应用前景，为进入该行业或有兴趣的读者提供参考。 1、传统的UPS供电系统 1.1、传统UPS供电发展 不间断电源是随着电子计算机的发展而发展的，由最初纯机械机构逐渐改变成为科技含量高且电子集成的电气设备，不间断电源的历史至今也不过几十年的历史。在不间断电源（UPS）发展经历了四代：第一代UPS电源—动态UPS：利用机械惯性储能以及电动机、发电机的能量传输机制以提供短时间的不间断供电，这种早期产品体积庞大、造价昂贵、噪声巨大，犹如一个小型电厂。第二代UPS电源—工频UPS电源机。工频UPS电源机目前常用于功率较大、用电环境较差的场合。第三代UPS电源—高频UPS电源机。高频机的出现进一步提升了功率密度，体积减小了50%，从功能模块上提升了维护性，缩短了MTTR时间，可在数小时内完成修复。第四代UPS电源—模块化高频UPS电源。高频机技术的发展为UPS的模块化架构提供了技术可能，结合类似通信电源的模块冗余技术的供电架构，模块化的高频UPS得以实现。 1.2、传统UPS供电方案 传统的UPS电源有一定的特点，它们虽然原理上简单，构造元件却比较多，除了燃料机和发电机之外还有整流器、飞轮等结构。新型的UPS电源不会出现这种情况，它将所有起作用的组成部分集合在一个规则的箱体里，运输、操作及安装在都非常简单。 传统的数据中心的电源系统是UPS系统，当电网掉电时，蓄电池经过逆变器变换为交流电供给负载，主要有3种供电方式。 1）串联热备份UPS供电方式。如图1所示，串联热备份UPS供电方式为2个UPS串联，但由于旁路开关的控制，其中只有1个UPS对负载供电，2个UPS互为备份，消除了单点故障，但存在超载能力差、备机老化不均等问题。 图1

物流系统flexsim仿真实验报告

物流系统f l e x s i m仿真 实验报告 文件排版存档编号：[UYTR-OUPT28-KBNTL98-UYNN208]

广东外语外贸大学 物流系统仿真实验 通达企业立体仓库实验报告 指导教师：翟晓燕教授专业：物流管理1101

目录

一、企业简介 二、通达企业立体仓库模型仿真 1.模型描述： 仓储的整个模型分为入库和出库两部分，按作业性质将整个模型划分为暂存区、分拣区、储存区以及发货区。 入库部分的操作流程是： ①.（1）四种产品A，B，C，D首先到达暂存区，然后被运 输到分类输送机上，根据设定的分拣系统将A，B，C，D分拣到 1，2,3,4，端口； ②.在1,2,3,4，端口都有各自的分拣道到达处理器，处理 器检验合格的产品被放在暂存区，不合格的产品则直接吸收掉； 每个操作工则将暂存区的那些合格产品搬运到货架上；其中，A， C产品将被送到同一货架上，而B，D则被送往另一货架； ③.再由两辆叉车从这两个货架上将A/B，C/D运输到两个 暂存区上；此时，在另一传送带上送来包装材料，当产品和包装 材料都到达时，就可以在合成器上进行对产品进行包装。 出库部分的操作流程是：包装完成后的产品将等待被发货。 2.模型数据： ①.四种货物A，B，C，D各自独立到达高层的传送带入口端：

A:normal(400,50)B:normal(400,50)C:uniform(500,100)D:uniform(500,100) ②.四种不同的货物沿一条传送带，根据品种的不同由分拣 装置将其推入到四个不同的分拣道口，经各自的分拣道到达操作 台。 ③.每检验一件货物占用时间为60,20s。 ④.每种货物都可能有不合格产品。检验合格的产品放入检 验器旁的暂存区；不合格的吸收器直接吸收；A的合格率为95%， B为96%，C的合格率为97%，D的合格率为98%。 ⑤.每个检验操作台需操作工一名，货物经检验合格后，将 货物送至货架。 ⑥.传送带叉车的传送速度采用默认速度（包装物生成时间 为返回60的常值），储存货物的容器容积各为1000单位，暂存 区17,18，21容量为10； ⑦.分拣后A、C存放在同一货架，B、D同一货架，之后由 叉车送往合成器。合成器比例A/C : B/D : 包装物 = 1： 1 ：4 整个流程图如下： 3.模型实体设计

高压直流供电

高压（240V及以上）直流IDC机房供电方案 高压直流供电系统从提出到实施已有3到5年时间了，其优点在这就不再罗列，相信各位都有了解，比如节能、维护方便等，但也存在一些致命弱点，比如浮地输出绝缘问题、割接安全性问题等，下面我们主要讨论一下直流IDC机房供电方案。 目前IDC机房内服务器基本采用交流输入，主要由UPS通过如并机冗余n+1系统、串并联冗余、双总线、双回路等系统供电方式来提供可靠供电，但往往导致整个系统复杂多变，增加了维护难度和成本。而高频直流模块化开关电源已是成熟产品，供电模式简单、维护方便、成本低、效率高，但与-48伏系统又存在一定差别，主要是一、电压高，操作危险性大； 二、高压直流供电系统输出浮地，对线缆耐压和绝缘程度要求高；三、由于高压直流供电是对现有交流服务器不改造实施，供电安全性可靠性必须有充分认证后再实施，避免引起服务器自带AC-DC变换器高低压保护而停止服务。 至于供电方案仍以分散供电为主，我初步考验以下几种： 一、单系统双路由方式：（目前机房-48V传输供电方式） 该供电方式与目前机房-48V传输供电方式一样，由一套系统提供两路主、备高压 直流电源。 优点：1、采用一套高压直流系统，结构简单，成本低。 2、输出采用双回路，可靠性较高。 3、效率高，但系统负载率可达70%以上。 缺点：仍存在单点故障隐患。

二、双系统双路由供电方案：（类似UPS并机冗余n+1系统） 优点：采用两套系统，可靠性高。 缺点：1、投资大、结构复杂。 2、效率低，但系统负载率必须控制在40%以内。 三、不同系统双路由供电方案：

优点：采用两套不同系统，可靠性高。可在现有系统中实施改造，增加一套高压直流系统，对重要双电源输入服务器实施改造 缺点：1、投资大、结构复杂。 2、效率低，但系统负载率必须控制在40%以内。

数据机房高压直流供电模式的探讨

数据机房高压直流供电模式的探讨 中国移动通信集团

前言 随着我国通信行业的高速发展，数据业务快速增加，传统的UPS供 电系统的大量应用加剧了通信局站的供电压力，增大了安全隐患，也 加大了设备维护工作量。 而众所周知直流供电系统的可靠性要高于UPS供电系统，那么我们 能不能找到一种新的供电系统来取代UPS供电系统，消除人们的顾虑 呢。因此我们对一种新型的高压直流供电系统做一些应用探讨。

前言 而自上世纪80年代以后，很多国家都在研究和实施300 ￣400V高压直流(HVDC)供电系统。在INTELEC上经常发布有各国的相关研究论文： 1999年日本代表提出《290V直流供电系统是电信和数据高效和可靠的供电系统》 1999年法国电信和阿尔卡持公司提出《供电给新的电信网络和服务用的新的供电系统》 2000年又发表了《用于电信和数据融合的整流型AC供电的新方法》 2007年发表了美国《在电信和数据中心改进能源效率的400V直流供电系统的评估》 2007年瑞典《在Gnesta市数据中心运行一年的9kW HVDC UPS供电系统》等等论文。

目录 传统的UPS供电模式 高压直流供电的可行性 高压直流供电的特点 高压直流供电的实例

传统的UPS解决方案 Uninterruptible Power System的缩写UPS，也就是不间断电源系统。在通信行业中，我们所说的UPS供电系统通常指的是交流用不间断电源系统。 就是当市电正常输入时，UPS通过整流、逆变为负载提供高质量的交流电源，同时其整流部分对蓄电池组进行充电； 当市电中断（事故停电）或输入故障时，由UPS蓄电池 组进行放电，通过逆变部分持续为负载提供高质量的交流电源，使负载维持正常工作。

数据中心的高压直流之路

数据中心得高压直流之路 1.引言 传统得数据中心大都通过UPS来实现掉电保护,通常所有ＩT负载都要经过UＰS来供电,假定实际运行ＵPS得平均效率为９0%(虽然目前UPS最高效率就是可以达到9５％以上，但我们知道UPS得效率与负载率有关，如左下图所示,随着负载率得提升,效率才会变高，那么正常情况2０％—4０%负载率下很难会达到最高效率点。根据在运行UPS得实际测试数据，绝大多数情况下得效率不高于90%）,那么每１００度电，经过UPＳ这个环节就白白损耗掉1０％。不仅如此，我们还需要考虑UPS散发出来得热量需要额外得空调带走,按数据中心典型PUE为1、８来算，那么ＵPＳ环节带来得总能耗达18%，很不节能。 （a)UPＳ效率与负载率得关系（b)传统机房得能耗分布我们还知道ＵPS设备得拓扑结构比较复杂，因此其单机可靠性一直不就是很高。为了解决单点故障问题，通常会引入2Ｎ,甚至2*(N+1）得冗余配置,那么这种情况下,虽然一定程度上提升了整个系统得可靠性，但带来得问题其实不少.首先,投资成本双倍增加,而且占用了很多机房得宝贵空间，并增加了运维得复杂度.其次，同前面解释过得一样,UＰS系统得负载率在2N情况下会比较低，此时UPS得效率也很低,额外增加了不少电费开销并浪费了很多宝贵得能源。最后,单机UPS得容量可能不够大,那么往往会采用并机模式，同样由于ＵPＳ自身结构得复杂性，且并机要求幅度、频率、相位等同,加上并机板自身也为单故障点，并机风险较大. 很多实际发生得案例表明在市电电网正常情况下，但因UPS自身故障引起机房掉电情况。UPＳ就是大容量危险设备,其内部电容等元件寿命只有五年，因此电容击穿、漏液短路等危险也时有发生,轻则造成系统宕机，重则导致机房着火，而且出了事故，第一时间现场无法处理，严

Flexsim实验报告实验二：流水作业线的仿真讲解

Flexsinm实验报告

实验目的 通过此实验掌握Flexsim 软件的基本用法，了解系统仿真的基本原理，运用Flexsim 进行模型的建立和仿真分析，通过实际建立仿真模型深刻认识仿真的基本概念。在学会运用Flexsim 进行几个模型的建立和仿真的基础之上进行自主分析，完成一定的探究过程，更好地将Flexsim 软件和现实紧密联系起来，以此为基础将更好地在物流中心的设计与运作方面进行统筹计划。其中包括： ? 掌握离散系统仿真的基本原理。 ? 掌握Flexsim 软件的基本操作和常用实体的参数设置等。 ? 掌握分析流程，建立模型的方法。 ? 掌握模型运行的基本统计分析方法。 ? 统计对象的选择和模型运行过程中被选择对象统计数据的输出和分析。 ? 通过实际建立仿真模型认识仿真的基本概念、感受仿真的情境。 ? 通过实际建立仿真模型认识仿真的基本概念、感受仿真的情境。 1、 实验内容 本次实验中，我们利用flexsim4.0软件平台，来仿真一个流水加工生产线系统，不考虑其流程间的工件运输，对其各道工序流程进行建模。 建立一个如下描述的流水加工生产线系统： 两种工件L_a 、L_b ，分别以正态分布(10,2)和均匀分布(20，10)min 的时间间隔进入系统，首先进入队列Q_in 由操作工人进行检验，每件检验用时2min 。不合格的废弃，离开系统，合格的送往后续加工工序，合格率为95%； L_a 送往机器M1加工，如需等待，则在Q_m1队列中等待；L_b 送往机器M2加工，如需等待，则在Q_m2队列中等待； L_a 在机器M1上加工时间为均匀分布(5,1)min ，加工后的工件为L_a2；L_b 在机器M2上的加工时间为正态分布(8,1)min ，加工后的工件叫做L_b2； 一个L_a2和一个L_b2在机器Massm 上装配成L_product ，需时为正态分布(5,1)min ，然后离开系统。 如装配机器忙则L_a2在队列Q_out1中等待；L_b2在队列Q_out2中等待； 并且让该系统运行一个月，直到流水线中的某个生产资料暂存区达到了其最大容量，则系统停滞加工。 该系统的运行效率指标由生产线的最长加工时间和最 M2 M1 Q_out2 Massm

高压直流电源

基于SG3525的3KW逆变电源设计 作者姓名：潘传义电子信息工程一班 指导教师：王生德 本电路利用48V直流蓄电池，可为后端提供3KW，2000V的高压直流电源。本电路设计的初衷是为电子捕鱼器后端产生脉冲波提供2000V直流电压。 本文对开关电源常用的电力电子器件做了简单介绍，重点介绍了 SG3525芯片的内部结构及其特性和工作原理，介绍了开关管MOSFET 的工作原理和开关动态特性等。设计了一款基于SG3525的推挽式DC-DC开关电源，提供高达2000V的直流电压。给出了系统的电路设计方法以及主要电路模块的原理分析和参数计算，特别是对开关电源高频变压器的设计给出了详尽的原理分析和各个参数的详细计算。 本电路采用推挽式开关变换，利用SG3525作为主要的控制芯片，产生两路互补的PWM方波脉冲控制开关管的通断。为提高PWM脉冲的驱动能力，加入桥式功率放大电路。滤波整流电路则采用桥式整流，RC滤波电路。另外，开关管工作频率高达25kHz，为此设计了RCD缓冲电路。考虑到电路环境的复杂性以及元器件的误差，电路在设计时对部分参数留有较大余量。 本电路的不同之处在于：采用两组相同的推挽变换电路且输出串联的设计，对变压器和整流滤波电路进行了有效的分压。产生高电压的同时，并没有大幅提高元器件的耐压要求，从而降低了对各种电力电子器件参数的要求。因而也使得电路的稳定性和可靠性更高。

本电路实现了从直流48V电压逆变到2000V直流电压的DC-DC变换供后续电路使用。本电路技术指标为：1）输入电压：蓄电池提供直流48V；2）输出电压：额定直流2000V；3）输出功率：最大3000W；4）输出波纹：无特殊要求，因此无需稳压电路。该系统工作过程：第一阶段：48V直流输入电压Ui经推挽电路变换成高频交流方波电压； 第二阶段：产生的交流方波电压经整流滤波电路分别产生1000V 直流电压，串联后实现2000V直流输出。 实验结果表明，该电源具有效率高，输出有效电压满足设计要求且运行可靠等优点。

微模块数据中心优势分析

微模块数据中心优势分析 随着“互联网+”“中国制造2025”等国家战略的全面深化，云计算、大数据、物联网、移动互联网等新兴产业迅猛发展。在此推动下，国内云计算数据中心的数量与建设规模日益增长，建设等级和单机柜功率密度也逐渐趋高。全面规划、分期建设、快速部署、灵活扩展、高可用性、低 PUE 值和最优TCO，一直是各行业用户的核心需求。微模块数据中心具备集约、绿色、安全、高效的优势，能有效满足超大型、大型、小型数据中心快速部署和分期建设的需求。 1.微模块方案概述 每一套微模块就是一个标准的数据中心，包含IDC数据中心应具备的供配电系统、制冷系统、综合运维管理系统、消防系统，各微模块之间相互独立性，运行时互不干扰，IT设备稳定性和可靠性得以提高。 微模块基础设施如基础底座、框架、电池柜、电池组、IT机柜、顶部封闭反板、通道门、闭门器等能在工厂按统一标准配备和预制。设计者根据用户 IT 机柜负荷要求，通过ICEPAK、6SigmaET、Flotherm软件建模，按照IT负荷散热和进排风需求，优化设计有组织散热和进排风模型，为用户快速定制最优方案。最优方案结合工厂预制的优势，缩短方案设计和现场组装时间，最大化的提高交付速度。 1.1模块化设计理念 模块化设计理念贯彻园区、楼层及机房三个层面，各层面相辅相成，匹配得当，让数据机房达到合理规划、节约投资、施工便捷、智能运维的效果。

表1机房微模块设计理念 1.2传统建设模型 国内数据中心机房大部分仍采用传统的地板下送风+冷热通道隔离+冷通道封闭的非框架式模块化设计，根据电源及空调设备摆放位置的不同，大致可以划分为电源及空调均内置、电源及空调均外置、电源外置空调内置三种模型。这三种模型均采用了冷通道封闭，制冷方式可采用地板下送风或者行间空调就近送风两种模式，在单列机柜数量不多或单机架功耗不高的情况下，可以将UPS及蓄电池内置在模块内部。在施工安装时，这三种模式通常都要求做 600mm高架空地板，且所有设备的机墩需要焊接固定，整体建设周期长，不易拓展。 1.3微模块应用方案及典型配置 相对传统建设模型，微模块数据中心能改善施工繁琐周期长，统一质量标准，解决机房末端智能运维的问题。框架式微模块相对非框架微模块，能更好的实现集成化、定制化和工厂预制，以适应中高功率密度及未来整机柜（云柜）的应用需求，本文以框架式微模块数据中心的优势展开讨论。 根据单机柜功率密度不同，框架式微模块也可以分为高、中、低三类方案，以高功率密度框架式微模块应用方案为例阐述三种模式。

恒流高压直流电源

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也就是说使除尘器的伏安特性的正阻区得到了大幅度的延伸，延伸的幅值取决于除尘器的状态和工况条件，一般含尘浓度大、电阻率高的烟尘，除尘器机械缺陷较大的，其伏安特性延伸幅值也大，而且延伸是在r=du/di→0附近，也就是说电压增加几千伏，电流成倍地增加。 从图一、图二的伏安特性可以看出，由于除尘器是具有气体放电特性的一个非线性特性，特别是曲线的后半段具有负阻特性，因此对于同一个电压值，电流可能是多值的，而对同一个电流值来说，电压是单值的，即在某一时刻，除尘器的工作电压是其电流的单值函数，因此，简单地从非线性电路平衡状态的稳定性来考虑，以恒流源来供电时，电压不会发生跳跃，可以稳定工作在r=du/di→0附近，即工作在高的电压和电流下，因为一个电流值，只有一个电压所对应，而电流值是由设备所决定的，因此这种稳定的工作状态不需要反馈控制回路来支撑，而且是本身回路所具有的。所以，用恒流源供电，可以使除尘器工作在较高的功率水平下

高压直流电源系统

高压直流电源系统产品 产品介绍 CP DUM27—240/400型通信用高压直流开关电源系统概述 DUM27—240/400型通信用高压直流供电系统包含交流配电部分、高频开关整流模块、直流配电部分和监控单元组成的柜式直流电源系统。是集有源功率因数校正技术、高频脉宽调制技术、软开关技术、单片机控制技术于一体的高新技术产品。可广泛适用于原交流UPS的所有应用环境，且具有更可靠，更省电，更节省投资的优势。 性能特点 ●高功率密度，单供电柜容量可达120KW ●输入高功率因数，低谐波电流 ●优秀的环境适应能力，宽的电压适应范围 ●完善的监控功能及成熟的电池管理功能 ●扩容灵活，维护方便，模块可热插拔 系统组成 ● CP DPJ05-380/630型交流配电屏 ● CP DUM27-240/400 型高压直流开关电源系统 ● CP DPZ03-240/1000 型高压直流配电屏

● CP DMA10-240/40型高频开关整流器（安装入模块架） ● CP DKD12型监控器（安装入模块架） 主要技术指标 CP DMA10-240/40型高频开关整流器?? 工作环境温度?-5℃～+50℃???????????????????? 交流输入参数 电压：三相三线制?380V±20％ 频率：45～65Hz 功率因数：≥0.93 开机浪涌电流：≤20A 输入电流谐波THD：≤9% 电磁干扰：符合GB 9254-1988 直流输出参数???????????? 额定电压：220V 电压范围：190V-286V 输出电流：额定值40A(输出电压286V时) 额定功率：10,000W (AC≥323V) 效率（满载测试）：≥93％ 限流选择范围：3－42A 均分负载不平衡度：≤±2.5％ 电网调整率：≤±0.1％ 负载调整率：≤±0.5％ 稳压精度：≤±0.6％ 温度系数：≤0.02％/℃ 纹波系数: ≤±0.2％ 峰—峰杂音电压：≤200mV； 可闻噪声：≤50dB（A）。

高压直流电源技术的发展现状及应用通用版

安全管理编号：YTO-FS-PD451 高压直流电源技术的发展现状及应用 通用版 In The Production, The Safety And Health Of Workers, The Production And Labor Process And The Various Measures T aken And All Activities Engaged In The Management, So That The Normal Production Activities. 标准/ 权威/ 规范/ 实用 Authoritative And Practical Standards

高压直流电源技术的发展现状及应 用通用版 使用提示：本安全管理文件可用于在生产中，对保障劳动者的安全健康和生产、劳动过程的正常进行而采取的各种措施和从事的一切活动实施管理，包含对生产、财物、环境的保护，最终使生产活动正常进行。文件下载后可定制修改，请根据实际需要进行调整和使用。 1 高压直流电源的基本工作原理和应用 高压直流电源是将工频电网电能转变成特种形式的高压电源的一种电子仪器设备，高压直流电源按输出电压极性可分为正极性和负极性两种。高压直流电源已经广泛应用于各行各业，农业领域也有应用，例如农业环境静电除尘，静电喷雾杀虫，农业物料静电喷涂包裹，农产品加工中的静电植绒、农业生物静电效应研究、静电杀菌、农业种子静电处理等等。随着农业科学技术的不断发展进步，农业科学研究和农业工程应用实践对高压静电电源的需求逐年增多，对其精度、性能、规格、品种、类型、体积、智能化操作等方面都提出了许多新的要求，现有的高压直流电源已经不能满足农业领域中的许多需要，研究和开发适合农业领域要求的多种新型直流高压电源已经成为一种客观需求，而且其社会效益和经济效益都比较显著，市场前景比较光明。

数据中心基础设施需求

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直流高压发生器使用说明书

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数据中心机房供电解决方案

数据中心机房供电 解决方案

中国移动正规划建设多个集团级和更多数量的省级数据中心,这些数据中心将优先采用云计算和虚拟化技术,以及仓储式、模块化机房的建设模式,具有规模大,用电负荷密度高、总功率大、空间紧凑等特点。同时集团公司对规划建设的数据中心提出了低成本、低能耗、扩展灵活的目标。因此对机房供电系统的可靠性、经济性、可扩展性、运行维护成本、节能环保和占地空间等提出了更高的要求。 本文经过对通信电源新产品、新技术应用分析,提出了新型全分散供电结构、336V高压直流电源和锂电池的应用,来实现建设高可靠性、高维护性、高效节能和高灵活性的数据中心机房供电系统。 新型全分散供电结构 一、新型全分散供电结构形式 新型全分散供电结构是指将不间断电源系统(含电池)分散安装在用电设备的列头或列间,就地为ICT设备供电。全分散供电系

统主要由电池柜、电源机柜和配电柜组成,其组成示意图如图1所示: 二、新型全分散供电结构特点 1、可取消电力电池室的建设,节约机房前期土建建设成本 由于将电源设备(含电池)分散到ICT设备机房内部安装,无需再单独设置电力电池室,这样可减少机房前期土建建设成本,更能提高机房的利用率; 2、柔性规划,按需扩容,实现边成长边投资的建设模式 选择模块化电源设备建设,电源系统容量能够根据机房的实际容量需求配置,逐步扩容,无需在建设初期一次性按最大容量建设,只要在机房初期规划好配电容量即可; 3、电源系统结构简单,可靠性高 从电源系统组成方面来看,全分散供电电源系统组成相对传统集中供电电源系统组成简单,系统可靠性非常高。全分散供电系统

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英文版直流高压发生器说明书

User manual book --High V oltage DC Generator

Warning People who use of this product must have a "high-voltage test certificate". Please read the 168 regulation of "electric power regulatory" when you use this product，and install two apparently disconnected point between power and the tester, when replacing the tester or Connecting line, you should break the two disconnect point of power supply. Check tester control box, the high-voltage cylinder and the grounding wire is connected together before testing. The grounding wire should be connected rightly to the earth. The large capacitor loader must discharged through the resistor of 100Ω/ V. Don’t contact the rod resistor with the loader immediately, you should put the rod resistor close to the sample gradually, keep a certain distance, and then discharge with hiss. When there is no sound, we can use rod resistor finally discharge by connecting to earth. If the loader is a capacitive loader, before test you must connect with resistor. When the voltage is more than 200kV, although the test personnel wear insulated shoes and at a safe distance from the outside area, but because of the effects of high voltage DC ion distribution of space electric field, it can lead to different DC potential of standing people nearby. Don’t handshake each other or touch any grounding body, otherwise there will be a mild electric shock phenomenon, this phenomenon happens in dry areas and winter commonly, but it generates little energy, so it can do no harm to people. After finishing the test, you must connect the grounding wire to the end of high voltage output, and then you can remove the lead wire off.

数据中心的高压直流之路教程文件

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